This description relates to systems that store and use energy. In one example, this relates to cameras that are triggered by motion sensors. These types of camera are commonly known as “trail cameras,” “wildlife cameras,” “game cameras,” “scouting cameras,” etc. One example of a trail camera is described in U.S. Pat. No. 6,735,387, which is incorporated by reference herein.
Typical trail cameras are powered by batteries, which must be replaced periodically. Trial cameras deplete batteries quickly. For example, trail cameral batteries may typically be changed within 60-90 days on some cameras.